146 Auroras and Sunset. 



would seem almost an impossibility that the air passing these 

 projections for a series of centuries, could have produced so high 

 a polish on so hard a substance, and in the total absence of all 

 ignigenous matter, it seems equally unaccountable that this effect 

 could have been produced by fire. I have broken off specimens 

 and brought them home, which have as high a polish and lustre 

 on the surface, as a piece of melted glass ; and then, as these 

 rocks have certainly been formed where they now lie, it must 

 be admitted that this strange effect has been produced either by 

 the action of the air, or by igneous influence, and if by the latter 

 cause, we can come to no other conclusion than that these results 

 are volcanic ; that this wall has once formed the side of an extin- 

 guished crater, and that the pipe stone, lying in horizontal strata, 

 was formed of the lava which issued from it. I am strongly in- 

 clined to believe, however, that the former supposition is the cor- 

 rect one, and that the pipe stone, which differs from all known 

 specimens of lava and steatite, will prove to be a subject of great 

 interest, and worthy of a careful analysis. 



I inclose you fair specimens of every character to be found in 

 the locality, and also a very slight outhne of the place, copied 

 from my original drawings. 



Very respectfully yours, &c. Geo. Gatlin. 



New York, March 4, 1839. 



Art. XVI. — Auroras and Sunset. 



I. Notice of an Aurora Borealis, as observed at Rochester, 

 N. Y.; by Prof. G. Dewey. 



The Aurora Borealis was splendid here as well as over the 

 country on Tuesday eve, Sept. 3d, 1839. It was distinguished 

 for its streams, and pillars, and cloudy-light — for centering at a 

 point a little S. and W. of the zenith, from which it seemed to 

 radiate in all directions, and extended greatly towards the south, 

 as well as from the north. The yellow, white, and crimson light 

 was splendid. There was no waving motion, like that in Jan., 

 1837. 



I have an account from an observer in the middle of the State 

 of Illinois, which may be reUed upon. It is as follows : 



